""I asked her questions trying to follow up on a better description of the suspects, she was unable to remember anything further about the suspects," the note from Durham police investigator B.W. Himan says, according to the motion."
http://www.wral.com/news/9276876/detail.html
So either she was never asked again to provide a description, or she was asked, and Nifong withheld that information.
I just read the article. So CGM apparently DID give an initial description of her attackers, and that is what the defense wants. Would Nifong have withheld it if it even vaguely matched the lacrosse players? Would the defense be pressing the question if they didn't already know the answer?